Old timers used low CW pitch for two reasons: You get "natural selectivity"
at low pitch, i.e. at a pitch of 200 Hz, QRM 200 Hz away will be at 400 Hz
(or at 0 Hz), which the ear can easily separate. At a pitch of 800 Hz the
same QRM will be at 1000 or 600 Hz. The other reason is that metallic
membranes of old style head-phones often had a natural resonance around 200
Hz, acting as "mechanical filters". Of course, with good filters, you no
longer need any of these tricks. So with a good rig, pitch is mostly a
matter of preference based on what your ears can hear best.
73,
George Wallner,
AA7JV
-----Original Message-----
From: topband-bounces@contesting.com [mailto:topband-bounces@contesting.com]
On Behalf Of BobK8IA@aol.com
Sent: Wednesday, November 29, 2006 10:21 AM
To: rtnmi@sbcglobal.net; Topband@contesting.com
Subject: Re: Topband: 160 mtr low signal - CW Pitch
In a message dated 11/29/2006 7:52:27 A.M. US Mountain Standard Time,
rtnmi@sbcglobal.net writes:
was just reading articles concerning low signal dxing and CW Pitch on the
160 meter band. Is there one pitch better than another
for this?
Here is what one well known Top Band DXer says:
Note: I like a very low CW pitch of 270 Hz for very weak signal DX-ing.
Please tell me what you think on this. I have an IC-775 es hit has pitch
control so it can be changed.
73 fer nw es gud DX,
QSL VIA: BUR, LotW, e-QSL
Bob AD5VJ(AAR6VM
--------------------------------------------------
I am not sure what it is, but during my nearly 50 yrs of hamming I have
always liked the lower pitch. There just seems to be more signal there.
Maybe its
my ears. I use about 350 Hz here.
73, Bob K8IA
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